- 4 tubes (2 x7-ml dry tubes with yellow gelose, and 2 x 5 ml tubes with blue CTAD) will be taken from the patient every 7 days following inclusion for 5 weeks (if the patient is still in hospital at the time), in the department where he/she is hospitalised (D7, D14, D21, D28, D35). Samples will no longer be taken once the patient has left the CHU, even if all of the samples have not been taken.